This invention relates, generally, to appliances and, more particularly, to appliances such as electric hair dryers, curling irons, kitchen appliances and the like which include a means for disconnecting the electrical current therein should the device become saturated with water to the point or for any other reason where a shock hazard exits.
The state of consumer appliances in present day households indicate that usage of electrical devices is increasing. There are many types of devices, particularly handheld types, which generally fall into three categories--health and beauty, kitchen and electric hand tools. Health and beauty handheld electrical devices are generally comprised of electric hair dryers, curling irons, electric razors; kitchen devices are generally mixers, blenders, coffee makers, etc.; while handheld electric tools are generally comprised of drills, hedge-clippers, handheld saws and the like.
The reason for the proliferation of these devices is quite simple. They are generally inexpensive to purchase, while being convenient and well adapted to their individual purpose. However, use of these devices produces a distinct danger, particularly when used around water, or even steel wool pads. This danger is in the form of electrocution. Frequency of electrocution as a result of these types of devices, particularly handheld electric hair dryers, is increasing. Since these types of devices are typically used in wet areas, such as by sinks, tubs or outside, it is readily apparent that there is a significant likelihood that the object will either be dropped into water, such as a bathtub or a sink, or that it may become contaminated with water, such as by splashes when clipping shrubbery by moisture which is present on grass, adjacent foundations or the like.
Presently, ground faulting interruptors are being used in new and renovation construction, which are expressly for the purpose of minimizing the chances of electrocution. However, these types of devices have not been integrated into existing housing, which comprises the bulk of usage areas. Hence, safety is a problem from place to place and not merely between devices.
Another significant and distinct disadvantage problem, whether or not conventional ground faulting directors are being utilized, is that fault current must generally flow through the user before the device detects and interrupts the flow of current therethrough. Another disadvantage is in the situation where there are no conventional ground fault interrupters and a separate interrupter is utilized with the device. Generally, conventional ground fault interrupters are somewhat bulky and cumbersome due to the fact that they not only detect and interrupt the flow of ground fault current, but also have user accessible test and reset buttons. This therefore drives up the cost and size requirements of any device wishing to utilize current interruptors.
Accordingly, it is an object of the present invention to provide a current path in a handheld electrical device which allows a current interruption device to operate more quickly.
It is a further object of the present invention to provide a current path in an electrically powered handheld device which avoids leakage current paths through the user of the device.
It is yet another object of the present invention to produce a device which incorporates a current interruption mechanism as an integral part thereof.
Yet another object of the present invention is to produce a handheld electrical device having current interruption integral therein wherein reset, once the device has been tripped, can only be accomplished by a special tool.
A still further object of the present invention is to produce a handheld electrical device having a current interrupting mechanism integral therein which is resettable only after inspection by a trained service person.
Yet another object of the present invention is to produce a handheld electrical device having an interrupting safety mechanism which is inexpensive to manufacture.
Another object of the present invention is to produce a device which adds few additional components and is easy to assemble.
Still a further object of the present invention is to produce a current interruption mechanism which is small and compact and may also fit into existing housing configurations and sizes.
Yet another object of the present invention is to produce a safety device which is retrofittable to existing designs. Such a device is taught by the present invention.
It is another object of the present invention to produce a safety device which will function even when the handheld device is not plugged in.
Finally, another object of the present invention is to produce a device having an electrical path for driving a load therein which comprises a ground plane disposed within the device in order to provide an electrical path, a detector with an input for detecting the presence of electrical current in the ground plane and an output for producing an electrical signal after detection of the presence of electrical current in the ground plane, and a current interruptor which has an input adapted to receive the output of the detector and an output for interrupting the electrical path in the device.